Lawyers are to challenge the detention of an Irish republican from Lurgan, County Armagh, in the European court.
Martin Corey, 63, has been in prison for over three years without a trial, and with no charges being brought.
He was sentenced to life in prison in 1973 for the IRA murders of two RUC officers.
He was released on licence in 1992, but just over three years ago his licence was revoked and he was returned to prison.
He was told he was being sent back to prison because he was considered a risk to the public.
But neither Martin Corey, a member of Republican Sinn Fein, nor his legal team have been told why he is considered to be a risk.
His lawyers are now taking the case to the European Court.
The Northern Ireland Office points out that Martin Corey's life licence was revoked by the Secretary of State following a recommendation by an independent Parole Commissioner.
When the case was referred to the Parole Commissioners in 2011, they could have directed his release if they "were satisfied that it was no longer necessary for the protection of the public from serious harm that he should be confined to prison".
They refused to do so, saying they were not satisfied that his detention was no longer necessary for the protection of the public.
However, his solicitor, Peter Murphy, said he was being denied the right to a fair trial.
"It's like internment all over again in the sense that he hasn't been given the chance to defend his position," Mr Murphy said.
"When we ask questions about the nature of the allegations and evidence against our client we are told nothing.
"In any criminal court you can meet your accuser, you have a chance to cross-examine them, and you have a chance to defend yourself because you're given the detail of what the allegations are against you.
"We don't have any of that, so our client is in a very difficult situation in that he's sitting in prison not knowing why he's there."
A spokeswoman for the NIO said Martin Corey's case is being reviewed again by the Parole Commissioners as part of their normal review processes.
His lawyers have challenged the secretary of state to bring charges against him to allow details of the allegations he faces to be heard in open court.